5.0 Non-Text Elements (Pictures, Images, Charts, etc.)

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1 5.0 Non-Text Elements (Pictures, Images, Charts, etc.) A. Provide Text Alternatives for all Non-Text Content The purpose of this guideline is to ensure that all non-text content is also available as a text description. Text refers to electronic text, not an image of text. Electronic text has the unique advantage of allowing information to be presented in many different formats. That is, it may be rendered visually, auditorily (spoken aloud), tactilely (Braille), easily enlarged, or in any combination. As a result, electronic text can be presented in whatever form best meets the needs of the user. The text description should convey the same information to the user that the image or picture conveys; it serves as an alternative representation of visual information in text format. The description should be short and to the point, while conveying equivalent information. It is not necessary to include the words, Image of in your text description. The assistive technology software will convey that information to the user, and it would be redundant to have that information in the text description as well. Rationale Providing text alternatives allows the information to be rendered in a variety of ways by a variety of user agents. For example, a person who cannot see a picture may have the text alternative read aloud using synthesized speech. A person who cannot hear an audio file may have the text alternative displayed so that he or she can read it.

2 33 Example When non-text content is provided, text alternatives for the non-text content should serve the equivalent purpose. Some text alternatives will describe the non-text content. For example, if an image of a screen shot shows a particular dialog box, an appropriate text alternative would be screen shot of Add Table dialog box. Other text alternatives will identify the purpose of the non-text content. For example, if a search button uses an image of a magnifying glass, an appropriate text alternative would be search and not magnifying glass. Exceptions If non-text content is intended to be purely decorative, an alternate text description is not necessary (it may even be distracting if there are a lot of decorative images in a document). In HTML, a document author would enter null alternate text, but this is not possible in Microsoft Word. The alternative is to ensure that the alternate text area is either blank (no description) or contains a filename that is intuitive. Providing both text alternatives and captions may be unnecessary and may provide redundant information to individuals who use screen reading programs. Whether to provide both text alternatives and captions will depend on the amount of information entered into the caption. If the caption provided provides sufficient information about the image, text alternatives are not necessary. If the caption does not sufficiently describe the image, text alternatives should be added to the image. If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives should at least provide descriptive identification of the non-text content. An example of a test or exercise that would be invalidated if presented in text is an audio-only spelling quiz. In this example, the text alternative might be, audio-only spelling quiz. If non-text content is primarily intended to create a specific sensory experience, then text alternatives must at least provide descriptive identification of the non-text content. An example of non-text content that is primarily intended to create a specific sensory experience is an audioonly recording of an orchestra. In this example, the text alternative might be recording of city orchestra. Steps to Provide Text Alternatives for Pictures, Images, and Clip Art: See Figure 18 1) Select the picture, image or clip art 3) Select Format Picture 4) Select Alt Text from the selections on the left of the Format Picture dialog box 5) Type the alternate text description into the Description: field 6) Select Close

3 34 Figure 18 : Steps to Provide Text Alternatives for Pictures, Images, and Clip Art Steps to Provide Text Alternatives for Shapes: See Figure 19 1) Select the shape 3) Select Format Shape 4) Select Alt Text from the selections on the left of the Format Shape dialog box 5) Type the alternate text description into the Description: field 6) Select Close Figure 19 : Steps to Provide Text Alternatives for Shapes

4 35 Steps to Provide Text Alternatives for SmartArt: See Figure 20 1) Select the SmartArt 3) Select Format Object 4) Select Alt Text from the selections on the left of the Format Shape dialog box 5) Type the alternate text description into the Description: field 6) Select Close Figure 20 : Steps to Provide Text Alternatives for SmartArt Steps to Provide Text Alternatives for Charts: See Figure 21 1) Select the chart 3) Select Format Chart Area 4) Select Alt Text from the selections on the left of the Format Chart Area dialog box 5) Type the alternate text description into the Description: field 6) Select Close

5 36 Figure 21 : Steps to Provide Text Alternatives for Charts Steps to Not Provide Text Alternatives for Decorative Images: See Figure 22 1) Select the decorative image 3) Select Format Picture 4) Select Alt Text from the selections on the left of the Format Picture dialog box If the information entered in the Description: field contains a file name that is intuitive (e.g., cartoon.jpg), leave as is and select Close If the information entered in the Description: field contains non-intuitive information (e.g., C:\Program Files\Microsoft Office\MEDIA\CAGCAT10\j wmf), erase the contents of the Description: field and select Close

6 37 Figure 22 : Steps to Not Provide Text Alternatives for Decorative Images B. Watermarks: Ensure Adequate Contrast and Add Text in the Document Watermarks can make reading the text in front of the watermark difficult and therefore present accessibility issues. Watermarks are a special form of WordArt and are stored as images. Beginning with Microsoft Word 2010, alternative text is automatically generated. However, the watermark is stored in the Header of the document which means that an individual using a screen reader will not have access to the watermark (or the alternative text associated with it) unless he or she knew to access the header of the document. Best Practice The use of watermarks should be evaluated. If there is a legitimate business need for a document author to use watermarks, then it is important that the following requirements be satisfied: Use a text-based watermark instead of an image-based watermark Expose the text of the watermark to the users by doing one of the following: Add the text of the watermark to the beginning of the document. For example, add the text, Document Status: Draft to the beginning of the document (or as close to the beginning of the document as is feasible) Include the text in the filename (e.g., Standards Document Draft) For all watermarks, regardless of whether they are text-based or image-based, ensure that there is adequate contrast between the text color and the color of the watermark

7 38 C. Provide Additional Descriptions for Complex Images/Charts If charts and graphs are complex and require additional explanation beyond what can be provided in the alternate text, provide this additional explanation in the surrounding text. Alternate text descriptions should be short and concise while conveying equivalent information. Some images and/or charts will require descriptions longer than should be entered into the alternate text description area. In these cases, it is appropriate to further explain the image or graph in the surrounding text. D. Place Graphics and Images In Line with Text Objects not placed in line with text are difficult to navigate to and may be inaccessible to people with vision disabilities. Screen readers can only detect and properly read the alternate text associated with objects when they are placed in line with text because objects that are not in line with text are not part of the text layer of the document (similar to text boxes). In addition, in line objects keep their position on the page relative to a portion of the text. Comprehension will be easier when the objects are located near (and are associated with) the surrounding text in which additional explanations may be contained. Steps to Place Graphics and Images In Line with Text : See Figure 23 1) Select the graphic or image 3) Select Wrap Text 4) Select In Line with Text

8 39 Figure 23 : Steps to Place Graphics and Images "In Line with Text" E. Avoid the use of Images of Text The intent of this standard is to require document authors to present information as text rather than using an image of text when they can achieve the same visual effect. This will enable people who require a particular visual presentation of text (e.g. a particular font size, foreground and background color, font family, line spacing or alignment) to be able to adjust the text presentation as required. If for any reason, the document author cannot format the text to get the same effect, then an image of text may be used. Exception If a particular presentation of text is essential to the information being conveyed, then it is acceptable to use images of text. Note: Logotypes (text that is part of a logo or brand name) are considered essential. When non-text content is presented as images of text, the text alternative shall be the text in the image. F. Do Not Use Text Boxes Text boxes are more like images than text and present accessibility issues. Text boxes are not part of the text layer of the document. Consequently, they are difficult to navigate to, and because they are not part of the text layer of the document, individuals using screen reading software will not know that the text box is in the document. Screen reading software is not able

9 40 to access information contained in a text box and it is very difficult, if not impossible, to access the object without a mouse. Best Practice Instead of using text boxes, convert the content of the text boxes to regular text. The visual effects of a text box can be achieved by using a bordered paragraph.